The aim of the study was to investigate the level of consciousness during the prehospital period of 299 persons killed in traffic accidents, and to determine the amount of lost years of life, during the period from January 1st 1986 to December 31st 1991. The study was a retrospective investigation based on police reports, medical records, death certificates and autopsy reports. The investigation was done in an area of Denmark without medically staffed prehospital care. The study demonstrates that the patients' cerebral condition worsened dramatically during the prehospital period. For these 299 killed persons a total of 10,368 years of life were lost, an average of 34.7 years per victim. One hundred and eighty-five persons between 18 and 65 years of age had a loss of 5,390 years of productivity. Medically staffed prehospital care at a high level ought to be built up in the whole country.